With the marked proliferation of computers and information technology, in particular, of the Internet, electronic-commerce transactions, for example, online stock trading, are being increasingly conducted. Generally, for electronic commerce, a customer interactively enters information required for conducting an electronic-commerce transaction (e.g., an item to be traded and a quantity of an item to be traded) through a graphical user interface (GUI) displayed on a client computer. Then, the client computer transmits entered information to a server over a network, and execution of an electronic-commerce program carries out the transaction. Operational error in such an information input causes incorrect orders. This becomes a cause of not only individual troubles but also a decreased reliability of electronic-commerce trading. Therefore, corporations that conduct electronic-commerce trading and companies in the computer industry that construct electronic-commerce systems have developed techniques for preventing an incorrect input.
Japanese Unexamined Patent Application Publication No. 2005-055951 discloses a technique that enables a complex web application having an input support function that can prevent erroneous input/registration to be easily generated from a framework of business specifications. This technique aims to greatly reduce development work of the web application and change maintenance work resulting from changes in the business specifications and thus greatly shorten a development period.
Japanese Unexamined Patent Application Publication No. 2004-194347 discloses a technique in which, when a predetermined program is selected from a still picture composed of size-reduced pictures shown as an electronic program guide, if the selected program is currently broadcasted, the program is immediately displayed, and if the selected program will be broadcasted in future, a detailed picture of the program is displayed.
Japanese Unexamined Patent Application Publication No. 9-016794 discloses a technique that successively determines a graphic to be selected by an operator while the operator is selecting the graphic, on the basis of a graphic specified by the operator, an operation command with selection of a graphic, and a parameter associated with the operation command, and visually feeds back the selected graphic in succession.
PCT Japanese Translation Patent Publication No. 2002-541588 discloses a user interface for an electronic trading system that allows a remote trader to view trends in the orders for an item, and provides the trading information in an easy to see and interpret graphical format.
Japanese Unexamined Patent Application Publication No. 9-237286 discloses a computer aided design (CAD) system that allows a user to establish various settings for the position and shape of an object with ease. According to this CAD system, a creator of a graphic drawing refers to a value set for a parameter displayed in a parameter field for use in execution of a selected command and finds the parameter required for the execution of the selected parameter. In response to an instruction to execute the command, the position and shape of an object is determined by use of the value set for the parameter and the object is placed in a graphic-drawing display area.
Japanese Unexamined Patent Application Publication No. 2002-122446 discloses an apparatus that can display measurement values without having to be upsized. In this apparatus, a standard display bar, an upper-limit alarm display bar, and a lower-limit alarm display bar are flashed in a display unit such that a standard value is set in consideration of the value of a measured current, voltage, power or the like, the upper-limit alarm value and the lower-limit alarm value are derived and set according to the magnitude of the standard value, or the standard value, upper limit alarm value, and lower limit alarm value are derived and set according to the magnitude of a set maximum scale value.
In the field of specific electronic commerce, for example, online stock trading, it is necessary to promptly enter data to the second to respond to a stock price, which changes every moment. Once data is transmitted and an electronic-commerce transaction is processed by a program, the cancellation of the trade is very difficult in general. Therefore, reversely entering a numeric value for a price of a share and that for the quantity of shares to be traded can possibly result in a critical loss, and such a situation actually occurred.